1. Technical Field
The present invention relates to a printing apparatus which has a function of generating job data based on input data, and a printing method.
2. Related Art
For example, JP-A-2005-63051 discloses a printing apparatus which continuously prints a plurality of pages, wherein preceding paper feeding where the next page starts to be fed in the course of printing the current page is performed so as to reduce a time interval from the printing completion of the current page to the printing start of the next page, thereby improving printing throughput.
The printing apparatus has a configuration where the preceding paper feeding command for the next page is incorporated into print job data in which the current page received from a host apparatus (upper-rank apparatus) is divided with the band units or raster units, and preceding paper feeding of the next page starts based on the preceding paper feeding command in the course of printing the present page.
However, in a case where the host apparatus is a portable information terminal, which has a relatively small storage capacity of the memory as compared with a personal computer (PC), it is not appropriate to install a printer driver having a considerable data size embedded in the PC in the portable information terminal. For this reason, a configuration is employed in which the printing apparatus side has the relatively important function of the printer driver, and the printing apparatus side processes display data received from the portable information terminal. For example, data including print setting information and image data is transmitted from the portable information terminal to the printing apparatus. The print setting information corresponds to print setting conditions and includes sheet kinds, sheet sizes, printing colors (color or monochrome), printing quality (high quality or draft), and the like.
In this case, the printing apparatus includes a print job conversion portion which generates print job data based on the print setting information and the image data of the data received from the portable information terminal, and a printing unit which generates engine control data by performing image processes for the image data of the print job data and controls a printing head and various motors based on the generated engine control data. The printing unit includes an image processing unit which generates the engine control data by performing image processes such as, for example, a resolution conversion process, a color conversion process, and a halftone process, and a printing engine which controls the printing head and various motors based on the engine control data and the like.
Contents of the image process or contents of the engine control performed by the printing unit are different depending on the print setting information. For this reason, before the printing unit performs the image processes or the engine control, it is necessary to perform an initialization process in advance so as to set initial values of parameters used for the image processes or initial values of parameters used for the control of the printing head or the motors. This initialization process (a setting process of processing conditions) is performed for each piece of data based on print setting information included in data received from the host apparatus such as a portable information terminal.
However, there are cases where print setting information is the same even in other pieces of data sent from the host apparatus. In these cases, although an initial value (the processing condition) of the parameter whose print setting information is set to be the same is the same, the printing unit performs the initialization process (the setting process of processing conditions) for each piece of data. Since the initialization process accompanies a relatively complicated operation, and thus takes a relatively long process time, there is a problem in that time from the data transmission start to the printing start by the printing apparatus becomes relatively long. To perform the initialization process in this way is a major factor delaying the printing start time. In addition, in a case as well where print job data is received from a host apparatus having the printer driver embedded therein, and printing is performed, if it is necessary to perform the initialization process for each piece of print job data, the same problem occurs even if there is a difference in the extent of the delays. Further, in a case as well where, in addition to data reception from the host apparatus, data is read from an external storage medium such as a memory card, or data read from a scanner is input if the printing apparatus is a multifunction machine, the same problem occurs.